GitLab MCP Server

create_branch

Create a new branch in a GitLab project by specifying the project, branch name, and source reference to organize development work.

Instructions

Create a new branch in a GitLab project

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "project_id": "<project_id>",
      "branch": "<branch>"
    },
    "name": "create_branch"
  }
}

Input Schema

Name	Required	Description
`project_id`	Yes	Project ID or complete URL-encoded path to project
`branch`	Yes	Name for the new branch
`ref`	No	Source branch/commit for new branch

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv1.0.0Jan 3, 2026
- addedInput schema / additionalProperties
```
Added value: +false
```
First observedNov 16, 2025

TDQS

C2.9/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool creates a branch but doesn't mention important behavioral aspects like required permissions, whether it's idempotent, error conditions, or what happens if the branch already exists. This leaves significant gaps for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that states the tool's purpose without unnecessary words. It's appropriately sized and front-loaded, with every word earning its place in conveying the core functionality.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutation tool with no annotations and no output schema, the description is insufficiently complete. It doesn't address behavioral aspects like permissions, error handling, or return values, leaving the agent with inadequate context to use the tool effectively despite the good parameter documentation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, providing clear documentation for all three parameters. The description doesn't add any parameter-specific information beyond what's in the schema, so it meets the baseline of 3 for adequate coverage without adding extra value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Create a new branch') and the resource ('in a GitLab project'), providing a specific verb+resource combination. However, it doesn't differentiate from sibling tools like 'create_merge_request' or 'fork_repository' that also create GitLab resources, which prevents a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing project), exclusions, or comparisons to related tools like 'create_merge_request' or 'fork_repository' in the sibling list.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.